Twitter said there was no evidence that data sold in recent days over the Internet was leaked by exploiting a security flaw in the company's systems.
The company had said that the data of 5.4 million accounts had been compromised due to a defect it discovered early last year, before it fixed it and revealed it in the summer.
Twitter said in a blog post that the other 600 million user data "cannot be linked to the previously reported incident, nor to any new incident."
"There is no evidence that data sold online was obtained by exploiting a vulnerability in Twitter's systems. It is possible that the data is a collection of data that is already publicly available on the Internet through various sources," he added.
And the social networking company told users last August that a vulnerability in the system revealed user accounts on Twitter by sending their email addresses or phone numbers after the company learned about it months ago.
Media reports claimed last December that someone had accessed more than 400 million emails and phone numbers of users linked to Twitter, and that the data had been leaked through the same security vulnerability discovered in January 2022.